GROWTH PATTERN AND PROBABILITY OF CAPTURE OF THE CRAB UCA TANGERI IN MBO RIVER, NIGERIA

Abstract

Studies on the growth pattern and probability of capture of the crab Uca tangeri in Mbo River of Akwa Ibom
State, Nigeria, was conducted for 12 consecutive months (April 2012 – March 2013). Length-frequency data was
analyzed using FiSAT software. Using Shepherd's method, asymptotic length (L∞) was 3.99cm, while the Von
Bertalanffy Growth Function (VBGF) K was 0.10. Meanwhile, Powell-Wetheral plot estimated asymptotic length
(L∞) was 3.58cm and Z/K was 0.72yr1. The natural mortality (M) of Uca tangeri was 0.71yr1. However, using
a length-converted catch curve, total mortality (Z) was estimated to be 0.27yr-1. The instantaneous fishing
mortality (F) was calculated to be -0.44yr-1, indicating that it was not a highly fished species.